Work machine and display system

ABSTRACT

A work machine comprises a body, a ripper apparatus that is disposed behind the body, and an imaging device that is mounted to the body and images the ripper apparatus. The ripper apparatus includes a shank, a ripping tip that is attached to an end of the shank, a beam that supports the shank, and a ripper arm that interconnects the body and the beam. The imaging device images the ripper apparatus sideways and captures an image in a range including at least a portion of the shank, at least a portion of the beam, and at least a portion of the ripper arm.

This nonprovisional application is based on Japanese Patent Application No. 2022-049946 filed on Mar. 25, 2022 with the Japan Patent Office, the entire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The present disclosure relates to a work machine and a display system.

Description of the Background Art

Japanese Patent Application Laying-Open No. 2017-082415 discloses a display system for displaying information of a work vehicle. An imaging unit is mounted on the body of the work vehicle and images a ripping tip. An image generation unit generates a display image including an image of the ripping tip captured by the imaging unit and information of rotation of a crawler belt. A display unit displays a display image.

SUMMARY OF INVENTION

According to the technology described in the above document, while an operator who views the display image can accurately grasp the position of the ripping tip and determine whether the crawler belt idles or shoe slip is caused, in order to perform an appropriate ripping operation, it is required that the operator can easily grasp the attitude of a ripper apparatus.

In the present disclosure are proposed a work machine allowing an attitude of a ripper apparatus to be easily grasped and a display system that displays a captured image of the ripper apparatus.

A work machine according to the present disclosure comprises a body, a ripper apparatus that is disposed behind the body, and an imaging device that is mounted on the body and images the ripper apparatus. The ripper apparatus includes a shank, a ripping tip that is attached to an end of the shank, a beam that supports the shank, and a ripper arm that interconnects the body and the beam. The imaging device images the ripper apparatus sideways. The imaging device captures an image in a range including at least a portion of the shank, at least a portion of the beam, and at least a portion of the ripper arm.

The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view schematically showing a configuration of a work machine according to an embodiment.

FIG. 2 is a rear view of the work machine shown in FIG. 1 .

FIG. 3 is a perspective view of a ripper apparatus.

FIG. 4 is a schematic diagram showing a first example of an image captured by an imaging device.

FIG. 5 is a schematic diagram showing a second example of an image captured by the imaging device.

FIG. 6 is a schematic diagram showing a third example of an image captured by the imaging device.

FIG. 7 is a block diagram generally showing a configuration of a display system according to an embodiment.

FIG. 8 is a schematic diagram showing an example of an image displayed on a display device.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, an embodiment will be described with reference to the drawings. In the following description, identical components are identically denoted. Their names and functions are also identical. Accordingly, they will not be described repeatedly in detail.

[Work Machine]

First, a configuration of a crawler dozer 100 will be described as an example of a work machine of an embodiment. FIG. 1 is a side view schematically showing a configuration of a work machine according to an embodiment. FIG. 2 is a rear view of the work machine shown in FIG. 1 .

As shown in FIGS. 1 and 2 , crawler dozer 100 mainly comprises a body 1, which corresponds to the body of the work machine in the embodiment, an excavating blade 2, and a travel unit 3. Excavating blade 2 is mounted to body 1. Excavating blade 2 is provided frontward of body 1. Travel unit 3 is a crawler belt type travel unit having a pair of right and left crawler belts 3C separated from each other in the vehicular widthwise direction. Body 1 is disposed between the paired right and left crawler belts 3C. Crawler dozer 100 travels as crawler belts 3C are driven.

Body 1 has a cab 9 and an engine compartment 8. Cab 9 is disposed at an upper rear portion of body 1. Engine compartment 8 is disposed frontward of cab 9. Engine compartment 8 is disposed between cab 9 and excavating blade 2.

In an embodiment, a direction in which crawler dozer 100 travels straight forward/backward is referred to as a forward/backward direction of crawler dozer 100. In the forward/backward direction of crawler dozer 100, a side on which excavating blade 2 projects from body 1 is defined as a forward direction. In the forward/backward direction of crawler dozer 100, a side opposite to the forward direction is referred to as a backward direction. A rightward/leftward direction of crawler dozer 100 is a direction orthogonal to the forward/backward direction in a plan view. When looking in the forward direction, a right side and a left side in the rightward/leftward direction are a rightward direction and a rightward direction, respectively. An upward/downward direction of crawler dozer 100 is a direction orthogonal to a plane defined by the forward/backward direction and the rightward/leftward direction. In the upward/downward direction, a side on which the ground is present is a downward side, and a side on which the sky is present is an upward side.

In FIG. 1 , the forward/backward direction is indicated by an arrow X, the rightward/leftward direction is indicated by an arrow Y, and the upward/downward direction is indicated by an arrow Z.

Crawler dozer 100 includes, as a work implement, excavating blade 2 (a first work implement) located frontward of body 1. Excavating blade 2 is a work implement for performing work such as excavation of ground surface and grading. Excavating blade 2 is an example of a frontward work implement disposed frontward of body 1. Excavating blade 2 has a lower end with a cutting edge 2C. Cutting edge 2C constitutes an edge of excavating blade 2. Excavating blade 2 has a left side end portion 2CL at a left end portion of cutting edge 2C. Excavating blade 2 has a right side end portion 2CR at a right end portion of cutting edge 2C. Excavating blade 2 has a left lower end 2E1 and a right lower end 2E2.

Excavating blade 2 has right and left sides both supported by a frame 4. Frame 4 is a member in the form of a quadrangular prism. Frame 4 has one end attached to a rear surface of excavating blade 2 by a rotatable support. Frame 4 has the other end rotatably supported on a side surface of travel unit 3.

Excavating blade 2 is driven by a tilt cylinder 5 and a lift cylinder 6. One end of tilt cylinder 5 is supported on a back surface of excavating blade 2 rotatably. The other end of tilt cylinder 5 is supported on an upper surface of frame 4 rotatably. Tilt cylinder 5 is extended/contracted by hydraulic pressure to cause an upper end of excavating blade 2 to move in the forward/backward direction about the support with which frame 4 is attached to excavating blade 2. Accordingly, the pitch angle of excavating blade 2 changes.

One end of lift cylinder 6 is supported on a back surface of excavating blade 2 rotatably. An intermediate portion of lift cylinder 6 is supported on a side surface of body 1. Lift cylinder 6 is extended/contracted by hydraulic pressure to cause excavating blade 2 to move in the upward/downward direction about the other end of frame 4.

A front grille 23 is attached to body 1. Front grille 23 is disposed at a front end of body 1. Front grille 23 is disposed to cover an opening formed at the front end of body 1. Excavating blade 2 is disposed frontward of and spaced from front grille 23.

At a rear end of body 1, a fuel tank 26 is disposed. Fuel tank 26 is disposed rearward of cab 9. In fuel tank 26, fuel to be supplied to engine 21 is stored.

As shown in FIG. 1 , fuel tank 26 is smaller in height toward the rear as seen in side view. Fuel tank 26 has a tapered surface inclined downward toward the rear.

Crawler dozer 100 includes a ripper apparatus (a second work implement) 10 as another work implement located rearward of body 1. Ripper apparatus 10 is a work implement for ripping through and thereby breaking a hard material such as rock. Ripper apparatus 10 is mounted to body 1. Ripper apparatus 10 is provided rearward of body 1. A side on which ripper apparatus 10 projects from body 1 in the forward/backward direction of crawler dozer 100 is the backward direction. Ripper apparatus 10 is disposed rearward of and spaced from fuel tank 26. Ripper apparatus 10 is an example of a rearward work implement disposed rearward of body 1.

FIG. 3 is a perspective view of ripper apparatus 10. As shown in FIGS. 1 to 3 , ripper apparatus 10 includes a shank 11 and a ripping tip 13. Ripping tip 13 is attached to an end (or a lower end) of shank 11. Ripper apparatus 10 causes ripping tip 13 to pierce a rock or the like to cut or crush the rock by traction force of travel unit 3. Ripping tip 13 is removable from shank 11. Ripper apparatus 10 is configured such that ripping tip 13 is replaceable.

Shank 11 is supported by a beam 17. Beam 17 has a holder 17H at a center position in the rightward/leftward direction to accommodate shank 11. A plurality of through holes 12 h are formed in shank 11. By inserting shank 11 into holder 17H and passing a holding pin 17P through any one of the plurality of through holes 12 h, shank 11 is fixed to beam 17, and beam 17 and shank 11 come to operate together.

Ripper arm 14 interconnects body 1 and beam 17. One end of ripper arm 14 is rotatably attached to a body frame 1F of body 1. Beam 17 is attached to the other end of ripper arm 14 via a connecting pin 14P rotatably with respect to ripper arm 14. Shank 11 is provided to be rotatable with respect to ripper arm 14 about connecting pin 14P together with beam 17.

Ripper apparatus 10 is driven by a tilt cylinder 15 and a lift cylinder 16. Tilt cylinder 15 and lift cylinder 16 are provided above ripper arm 14. Tilt cylinder 15 is disposed above lift cylinder 16. Lift cylinder 16 moves beam 17 and shank 11 up and down. Lift cylinder 16 moves ripping tip 13 up and down. Tilt cylinder 15 causes ripping tip 13 to reciprocate in a direction toward body 1 (i.e., the forward direction) and a direction away from body 1 (i.e., the backward direction). Tilt cylinder 15 changes the angle of shank 11 with respect to ripper arm 14. An angle formed by shank 11 with respect to ripper arm 14 is referred to as a tilt angle of shank 11.

As tilt cylinder 15 extends and contracts, an angle formed by shank 11 with respect to a target to be worked on by ripper apparatus 10, that is, the current topography, varies. As tilt cylinder 15 extends and contracts, an angle formed by shank 11 with respect to a horizontal direction varies. As tilt cylinder 15 extends and contracts, an angle formed by shank 11 with respect to a direction toward the vehicular body varies. The tilt angle of shank 11 may be defined as an angle formed with respect to the current topography, an angle formed with respect to the horizontal direction, or an angle formed with respect to the direction toward the vehicular body.

Tilt cylinder 15 has a proximal end rotatably attached to body 1 at body frame 1F. Tilt cylinder 15 has a distal end rotatably connected to beam 17 via a connecting pin 15P. Lift cylinder 16 has a proximal end rotatably attached to body 1 at body frame 1F. Lift cylinder 16 has a distal end rotatably connected to beam 17 via a connecting pin 16P. As shown in FIGS. 2 and 3 , beam 17 has a pair of left connecting portion 17L and a right connecting portion 17R. Tilt cylinder 15 includes a left tilt cylinder 15L and a right tilt cylinder 15R. Lift cylinder 16 includes a left lift cylinder 16L and a right lift cylinder 16R. Connecting pins 15P and 16P include left connecting pins 15PL and 16PL and right connecting pins 15PR and 16PR.

Left tilt cylinder 15L is connected to an upper end portion of left connecting portion 17L via left connecting pin 15PL. Left lift cylinder 16L is connected to left connecting portion 17L via left connecting pin 16PL. Right tilt cylinder 15R is connected to an upper end portion of right connecting portion 17R via right connecting pin 15PR. Right lift cylinder 16R is connected to right connecting portion 17R via right connecting pin 16PR.

Referring back to FIGS. 1 and 2 , an engine 21 as a driving source for crawler dozer 100 is accommodated in engine compartment 8. Engine 21 generates power which is in turn transmitted to a driving wheel of travel unit 3 via a drive train located inside body 1. As the driving wheel rotates, crawler belts 3C are driven, and crawler dozer 100 travels. Engine 21's power is also transmitted to a hydraulic pump. The hydraulic pump supplies pressurized oil to each actuator, such as tilt cylinder 5 and lift cylinder 6 that drive excavating blade 2, and tilt cylinder 15 and lift cylinder 16 that drive ripper apparatus 10.

Engine 21 is covered from above with an engine hood 22. Engine hood 22 forms a ceiling of engine compartment 8. Engine hood 22 isolates an interior of engine compartment 8 from outside thereof.

A working platform 30 is disposed above fuel tank 26. Working platform 30 is disposed rearward of cab 9. Working platform 30 is a scaffold for a worker to work behind cab 9. The worker works on working platform 30 for example to clean a window of cab 9, replace a filter of fuel tank 26 and maintain a breather, etc. A guardrail 31 is attached to working platform 30 to prevent unexpected fall.

Along a left edge of body 1, an access passage 40 is provided to enable access to working platform 30 from the ground. A guardrail 41 is attached to access passage 40 to prevent unexpected fall.

A roll-over protective structure 90 is attached to crawler dozer 100. Roll-over protective structure 90 is standardized as ISO3471. In the rear view shown in FIG. 2 , roll-over protective structure 90 is not shown for clarity of illustration. Roll-over protective structure 90 is provided in the form of a three-side frame.

Roll-over protective structure 90 has a left columnar portion 91, a beam portion 93, and a right columnar portion (not shown). Left columnar portion 91 is disposed on a left side of cab 9. The right columnar portion is disposed on a right side of cab 9. Beam portion 93 is disposed above cab 9. Beam portion 93 has a left end connected to an upper end of left columnar portion 91 and a right end connected to an upper end of the right columnar portion. Beam portion 93 is supported by left columnar portion 91 and the right columnar portion. Beam portion 93 extends in the rightward/leftward direction between left columnar portion 91 and the right columnar portion.

A plurality of cameras are attached to crawler dozer 100. The plurality of cameras include a first camera 51, a second camera 52, a third camera 53, a fourth camera 54 (not shown in FIGS. 1 and 2 ), a fifth camera 55, a sixth camera 56 (not shown in FIGS. 1 and 2 ), a seventh camera 57, and an eighth camera 58.

First camera 51 captures an image of a front side of and frontward of body 1. First camera 51 captures an image in a range including a range of the front side of and frontward of body 1. A captured image output by first camera 51 may include topography frontward of body 1. First camera 51 corresponds to a front imaging device in an embodiment. First camera 51 is attached on an upper surface of cab 9. First camera 51 projects upward from the upper surface of cab 9. First camera 51 is mounted to body 1 via cab 9. First camera 51 is fixed to face frontward.

Second camera 52 captures an image of a rear side of and rearward of body 1. Second camera 52 captures an image in a range including a range of the rear side of and rearward of body 1. A captured image output by second camera 52 may include topography rearward of body 1. Second camera 52 corresponds to a rear imaging device in an embodiment. Second camera 52 is attached to eaves 9 c projecting from cab 9 rearward. Second camera 52 is mounted to body 1 via cab 9. Second camera 52 is fixed to face rearward and downward.

Third camera 53 captures an image of left side end portion 2CL of cutting edge 2C of excavating blade 2. Third camera 53 captures an image in a range including left lower end 2E1 of excavating blade 2. A captured image output by third camera 53 may include left lower end 2E1 of excavating blade 2. Third camera 53 captures an image in a range including a point on the ground where left lower end 2E1 of excavating blade 2 penetrates a ground surface. Third camera 53 corresponds to a left blade imaging device in an embodiment. Third camera 53 is attached to left columnar portion 91 of roll-over protective structure 90. Third camera 53 is mounted to body 1 via roll-over protective structure 90. Third camera 53 is fixed to face frontward and downward.

Although not shown in FIGS. 1 and 2 , fourth camera 54 is attached to the right columnar portion of roll-over protective structure 90. Fourth camera 54 is mounted to body 1 via roll-over protective structure 90. Fourth camera 54 is fixed to face frontward and downward. Fourth camera 54 captures an image of right side end portion 2CR of cutting edge 2C of excavating blade 2. Fourth camera 54 captures an image in a range including right lower end 2E2 of excavating blade 2. A captured image output by fourth camera 54 may include lower right end 2E2 of excavating blade 2. Fourth camera 54 captures an image in a range including a point on the ground where right lower end 2E2 of excavating blade 2 penetrates a ground surface. Fourth camera 54 corresponds to a right blade imaging device in an embodiment.

Fifth camera 55 captures an image of a left side of and leftward of body 1. Fifth camera 55 captures an image in a range including a range of the left side of and leftward of body 1. A captured image output by fifth camera 55 may include topography leftward of body 1. Fifth camera 55 corresponds to a left imaging device in an embodiment. Fifth camera 55 is attached to left columnar portion 91 of roll-over protective structure 90. Fifth camera 55 is mounted to body 1 via roll-over protective structure 90. Fifth camera 55 is fixed to face leftward and downward. Third camera 53 and fifth camera 55 are disposed to be adjacent to each other in the forward/backward direction such that third camera 53 is on a front side and fifth camera 55 is on a rear side.

Although not shown in FIGS. 1 and 2 , sixth camera 56 is attached to the right columnar portion of roll-over protective structure 90. Sixth camera 56 is mounted to body 1 via roll-over protective structure 90. Sixth camera 56 is fixed to face rightward and downward. Sixth camera 56 captures an image of the right side of and rightward of body 1. Sixth camera 56 captures an image in a range including a range of the right side of and rightward of body 1. A captured image output by sixth camera 56 may include topography rightward of body 1. Sixth camera 56 corresponds to a right imaging device in an embodiment. Fourth camera 54 and sixth camera 56 are disposed to be adjacent to each other in the forward/backward direction such that fourth camera 54 is on a front side and sixth camera 56 is on a rear side.

Seventh camera 57 captures an image of ripping tip 13 corresponding to a lower end of ripper apparatus 10. Seventh camera 57 captures an image in a range including ripping tip 13. A captured image output by seventh camera 57 may include ripping tip 13. Seventh camera 57 corresponds to a ripping tip imaging device in an embodiment. Seventh camera 57 is attached to a rear surface of body 1. Seventh camera 57 is mounted to body 1 on a rear surface of body 1 in a vicinity of a center portion in the rightward/leftward direction. Seventh camera 57 is fixed to face rearward and downward.

Eighth camera 58 is mounted on a rear surface of body 1. Eighth camera 58 is disposed away from the center of body 1 in the rightward/leftward direction. Eighth camera 58 is disposed on a left side with respect to the center of body 1 in the rightward/leftward direction. Eighth camera 58 is disposed above left crawler belt 3C. Eighth camera 58 is disposed frontward of ripper apparatus 10 obliquely leftward. Eighth camera 58 is disposed to the left with respect to ripper apparatus 10 in the rightward/leftward direction. Eighth camera 58 is disposed frontward of shank 11 of ripper apparatus 10 and is disposed to be closer to the left than shank 11. Eighth camera 58 is disposed frontward of ripping tip 13 obliquely leftward in a plan view.

Eighth camera 58 captures an image of ripper apparatus 10. Eighth camera 58 is fixed to face rearward and obliquely rightward so as to be able to capture an image of ripper apparatus 10. Eighth camera 58 has an optical axis extending therefrom rearward and obliquely rightward. Eighth camera 58 captures an image of ripper apparatus 10 from a left side. Eighth camera 58 captures an image of ripper apparatus 10 in a direction including a component of the rightward/leftward direction. Eighth camera 58 captures an image of ripper apparatus 10 ahead thereof from an obliquely left side.

Eighth camera 58 captures an image in a range including at least a portion of ripper apparatus 10. A captured image output by eighth camera 58 may include at least a portion of ripper apparatus 10. Eighth camera 58 corresponds to an imaging device in an embodiment.

FIGS. 4 to 6 are schematic diagrams showing examples of images captured by eighth camera 58 (or the imaging device). As shown in FIGS. 4-6 , eighth camera 58 captures an image in a range including at least a portion of shank 11, at least a portion of beam 17, and at least a portion of ripper arm 14. Eighth camera 58 captures an image including information of a tilt angle of shank 11, an angle of beam 17 with respect to ripper arm 14, a distance of ripper arm 14 from a ground surface, an angle formed by ripper arm 14 with respect to a ground surface, etc.

Eighth camera 58 further captures an image in a range including at least a portion of tilt cylinder 15 (left tilt cylinder 15L). Left tilt cylinder 15L includes a cylinder tube 15Ls and a rod 15Lr. Rod 15Lr is supported by cylinder tube 15Ls reciprocatably relative to cylinder tube 15Ls along cylinder tube 15Ls. Eighth camera 58 captures an image in a range including at least a portion of cylinder tube 15Ls and at least a portion of rod 15Lr. Eighth camera 58 captures an image including information of by how much amount left tilt cylinder 15L extends and contracts, and hence information of a tilt angle of shank 11.

Eighth camera 58 further captures an image in a range including at least a portion of lift cylinder 16 (left lift cylinder 16L). Eighth camera 58 captures an image including information of by how much amount left lift cylinder 16L extends and contracts, and hence information of a distance of ripper arm 14 from a ground surface, an angle formed by ripper arm 14 with respect to a ground surface, etc.

With reference to FIG. 4 , an image 58IMG1 captured by eighth camera 58 shows lift cylinder 16 (left lift cylinder 16L) with a minimal length. Ripper arm 14, beam 17, and shank 11 assume the uppermost position in their possible range of movement in the upward/downward direction. Ripping tip 13 is located away from a ground surface and hence in the air.

With reference to FIG. 5 , an image 58IMG2 captured by eighth camera 58 shows lift cylinder 16 (or left lift cylinder 16L) larger in length than in FIG. 4 . Ripper arm 14, beam 17 and shank 11 are positioned below the position shown in FIG. 4 and are close to a ground surface. Although shank 11 is hidden by beam 17 and thus not included in the captured image, shank 11 is present within the range in which eighth camera 58 captures an image. Ripping tip 13 is still located away from a ground surface, and hence in the air.

With reference to FIG. 6 , an image 58IMG3 captured by eighth camera 58 shows lift cylinder 16 (left lift cylinder 16L) with a maximal length. Ripper arm 14, beam 17, and shank 11 assume the lowest position in their possible range of movement in the upward/downward direction. Ripping tip 13 is in the ground and thus not included in the captured image, however, ripping tip 13 is present within the range in which eighth camera 58 captures an image. As compared with FIG. 5 , tilt cylinder 15 (left tilt cylinder 15L) has rod 15Lr projecting from cylinder tube 15Ls by an increased length, and left tilt cylinder 15L thus has an increased length. The extension of left tilt cylinder 15L changes an angle of beam 17 and shank 11 with respect to ripper arm 14, and moves ripping tip 13 forward in the ground.

[Display System]

Hereinafter a display system of an embodiment will be described. FIG. 7 is a block diagram schematically showing a configuration of a display system according to an embodiment. As shown in FIG. 7 , the display system comprises crawler dozer 100 described with reference to FIGS. 1 to 3 , and a remote control station 101.

Crawler dozer 100 has a video controller 60. First to eighth cameras 51 to 58 are electrically connected to video controller 60. Video controller 60 receives from first to eighth cameras 51 to 58 data of an image captured by each camera. Video controller 60 includes an encoder 61 that compresses and encodes the data of the captured image.

Crawler dozer 100 includes an operation controller 63. Operation controller 63 controls an operation of crawler dozer 100 based on a program stored in a memory (not shown). Operation controller 63 controls an operation of excavating blade 2 by outputting a control signal to a blade actuator, that is, tilt cylinder 5 and lift cylinder 6. When tilt cylinder 5 and lift cylinder 6 receive the control signal from operation controller 63, tilt cylinder 5 and lift cylinder 6 appropriately extend and contract and thus change a pitch angle of excavating blade 2 and move excavating blade 2 up and down.

Operation controller 63 controls an operation of ripper apparatus 10 by outputting a control signal to a ripper actuator, that is, tilt cylinder 15 and lift cylinder 16. When tilt cylinder 15 and lift cylinder 16 receive the control signal from operation controller 63, tilt cylinder 15 and lift cylinder 16 appropriately extend and contract and accordingly, beam 17 and shank 11 move up and down, and ripping tip 13 at the end of shank 11 moves up and down and back and forth.

Operation controller 63 controls traveling of crawler dozer 100 by outputting a control signal to a transmission 64 and a steering device 66.

Crawler dozer 100 has a transmitting/receiving device 62. Video controller 60 sends a signal to remote control station 101 and receives a signal from remote control station 101 via transmitting/receiving device 62. Video controller 60 sends data of a captured image output from first to eighth cameras 51 to 58 to remote control station 101 via transmitting/receiving device 62.

Remote control station 101 is located outside crawler dozer 100. Remote control station 101 includes a display control device 110, a transmitting/receiving device 112, an input device 114, and a display device 120. Display control device 110, transmitting/receiving device 112, input device 114, and display device 120 are disposed in remote control station 101 remote from crawler dozer 100.

Display control device 110 controls display device 120. Display control device 110 receives a signal from crawler dozer 100 and sends a signal to crawler dozer 100 via transmitting/receiving device 112. Display control device 110 receives data of an image captured by first to eighth cameras 51 to 58 from crawler dozer 100 via transmitting/receiving device 112. Display control device 110 has a decoder 111 that decodes data compressed and encoded by encoder 61.

Display control device 110 causes display device 120 to display one or more captured images output from one or more of first to eighth cameras 51 to 58. In an embodiment described below, display device 120 is caused to display captured images output from four cameras out of those output from the eight cameras. Input device 114 is a switch that is operated to select a captured image that display device 120 is to display while the vehicle travels, stops, bulldozes and rips. Display control device 110 receives an input from input device 114 operated by an operator and causes display device 120 to display a selected, captured image.

Remote control station 101 also includes a console panel 140. Console panel 140 includes a blade operating lever 141, a ripper operating lever 142, and a steering lever 143. Blade operating lever 141, ripper operating lever 142, and steering lever 143 are manipulated by an operator. An operation done to console panel 140 is input to operation controller 63 of crawler dozer 100. When operation controller 63 receives the input of the operation of console panel 140, operation controller 63 in response thereto outputs a control signal to the blade actuator, the ripper actuator, transmission 64 or steering device 66 to operate these actuators.

Input device 114 and console panel 140 are arranged at a hand of an operator who views display device 120. The operator can operate input device 114 and console panel 140 to remotely operate crawler dozer 100 while viewing display device 120.

FIG. 8 is a schematic diagram showing an example of an image displayed on display device 120. Display control device 110 sets a plurality of divided display sections for display device 120. For display device 120 shown in FIG. 8 , a front display section 121, a rear display section 122, a ripping tip display section 127, and a ripper apparatus display section 128 are set as the plurality of divided display sections. Display device 120 shown in FIG. 8 displays an image to be displayed while ripper apparatus 10 performs a ripping operation.

Front display section 121 displays a captured image output from first camera 51 (or the front imaging device) that captures an image in a range including a range of a front side of and frontward of body 1. Rear display section 122 displays a captured image output from second camera 52 (or the rear imaging device) that captures an image in a range including a range of a rear side of and rearward of body 1. Ripping tip display section 127 displays a captured image output from seventh camera 57 (or the ripping tip imaging device) that captures an image in a range including ripping tip 13. Ripper apparatus display section 128 displays a captured image output from eighth camera 58 (or an imaging device) that captures an image in a range including at least a portion of ripper apparatus 10.

Display control device 110 sets ripping tip display section 127, rear display section 122, and ripper apparatus display section 128 such that the sections are aligned in this order from the left to the right. Display control device 110 sets front display section 121 above ripping tip display section 127, rear display section 122, and ripper apparatus display section 128 that are aligned.

Front display section 121 is set in the form of a laterally long rectangle. Rear display section 122 is formed in the same laterally long rectangle as front display section 121. Front display section 121 and rear display section 122 are set to have the same area. Display control device 110 sets front display section 121 and rear display section 122 to be vertically aligned such that front display section 121 is arranged on an upper side and rear display section 122 is arranged on a lower side. Display control device 110 sets front display section 121 and rear display section 122 so as to be centered.

Display control device 110 sets ripping tip display section 127 on a left side of the vertically aligned front display section 121 and rear display section 122. Ripping tip display section 127 is set in the form of a laterally long rectangle having a smaller area than rear display section 122.

Display control device 110 sets ripper apparatus display section 128 on a right side of the vertically aligned front display section 121 and rear display section 122. Ripper apparatus display section 128 is set in the form of a vertically long rectangle. Ripper apparatus display section 128 is set to be vertically longer than rear display section 122 and ripping tip display section 127. Ripper apparatus display section 128 is set on a right side of rear display section 122. An image of ripper apparatus 10 is displayed on a right side of an image of a rear side of and rearward of body 1 displayed in rear display section 122. Ripper apparatus display section 128 displays ripper apparatus 10 so as to project to the right from a left edge of ripper apparatus display section 128 adjacent to rear display section 122.

Display control device 110 sets a variety of types of icons 131, an inclinometer 132, and a tilt indicator 133 at an upper right corner of display device 120. Inclinometer 132 and tilt indicator 133 indicate a pitch angle and a roll angle of crawler dozer 100 with respect to a horizontal plane. A position at which inclinometer 132 and tilt indicator 133 are displayed is not limited to the upper right corner of display device 120. Inclinometer 132 and tilt indicator 133 may be superimposed on a captured image and thus displayed. Display control device 110 sets a camera position indicator 134 at an upper left corner of display device 120. The camera position indicator displays an arrangement of a camera that captures an image currently displayed on display device 120.

Function and Effect

Although there is a description which partially overlaps with the above description, a characteristic configuration as well as function and effect of the present embodiment will be summarized as follows:

As shown in FIGS. 1 to 3 , ripper apparatus 10 comprises shank 11, ripping tip 13 that is attached to an end of shank 11, beam 17 that supports shank 11, and ripper arm 14 that interconnects body 1 and beam 17. Eighth camera 58 images ripper apparatus 10 sideways. As shown in FIGS. 4-6 , eighth camera 58 captures an image in a range including at least a portion of shank 11, at least a portion of beam 17, and at least a portion of ripper arm 14.

An image captured by eighth camera 58 includes ripper apparatus 10 as viewed sideways. An operator who views the image captured by eighth camera 58 can easily grasp an attitude and movement of ripper apparatus 10. When ripping tip 13 is in the air and thus included in a captured image, the operator can grasp the current position and operation of ripping tip 13 by observing ripping tip 13 in the captured image. Even when ripping tip 13 is in the ground and thus not imaged, the operator can easily estimate the current position and operation of ripping tip 13 by checking the attitude of ripper arm 14 and the position and movement of beam 17 relative to ripper arm 14.

As shown in FIGS. 4 to 6 , eighth camera 58 may capture an image in a range including at least a portion of tilt cylinder 15. Eighth camera 58 may capture an image in a range including cylinder tube 15Ls and rod 15Lr of left tilt cylinder 15L. When ripping tip 13 is in the ground and thus not imaged, the operator can easily estimate the current position and operation of ripping tip 13 by checking by how much length rod 15Lr projects from cylinder tube 15Ls of left tilt cylinder 15L and how the length varies.

As shown in FIGS. 4-6 , eighth camera 58 may capture an image in a range including at least a portion of lift cylinder 16. Eighth camera 58 may capture an image in a range including the cylinder tube and rod of left lift cylinder 16L. The operator can easily grasp the current position of ripping tip 13 by checking by how much length the rod projects from the cylinder tube of left lift cylinder 16L in addition to what attitude ripper arm 14 and beam 17 assume.

As shown in FIGS. 1 and 2, and 4 to 6 , eighth camera 58 may image ripper apparatus 10 from a left side. When the operator aboard cab 9 looks back and sees ripper apparatus 10, the operator will see ripper apparatus 10 in a direction including a component of the rightward/leftward direction as the driver's seat in cab 9 is disposed closer to the left with respect to the center of body 1 in the rightward/leftward direction. Specifically, the operator will see ripper apparatus 10 from the left side. Disposing eighth camera 58 at the same position as the viewpoint of the operator aboard cab 9, that is, on the left side of ripper apparatus 10, allows an image captured by eighth camera 58 to match the sense of the operator. The operator can easily grasp the attitude of ripper apparatus 10 by viewing the captured image.

As shown in FIGS. 1 and 2 , crawler dozer 100 may further comprise seventh camera 57 that captures an image in a range including ripping tip 13, and second camera 52 that captures an image in a range including a range of the rear side of and rearward of body 1. The operator can grasp the position of ripping tip 13 with respect to a ground surface by viewing an image captured by seventh camera 57. The operator can grasp topography behind body 1 and whether any obstacle is present or absent behind body 1 by viewing an image captured by second camera 52.

As shown in FIG. 7 , the display system comprises crawler dozer 100 described above and display device 120. As shown in FIG. 8 , display device 120 simultaneously displays an image captured by seventh camera 57, an image captured by second camera 52, and an image captured by eighth camera 58. While display device 120 displays an image, the operator can grasp the state of the rear side of and rearward of body 1 by viewing rear display section 122 in the image, the position of ripping tip 13 by viewing ripping tip display section 127 in the image, and the attitude of ripper apparatus 10 by viewing ripper apparatus display section 128 in the image. The operator can obtain sufficient information from display device 120 and perform a ripping operation efficiently and safely.

As shown in FIG. 8 , display device 120 may be caused to display an image captured by seventh camera 57, an image captured by second camera 52, and an image captured by eighth camera 58 aligned from the left to the right. Rear display section 122 is disposed at a center of display device 120 between the left and right sides and ripper apparatus display section 128 is disposed on a right side of rear display section 122, and ripper apparatus display section 128 displays an image of ripper apparatus 10 captured from a left side. This allows display device 120 to display an image matching the sense of the operator.

As shown in FIG. 7 , display device 120 may be disposed outside crawler dozer 100. An operator can remotely monitor crawler dozer 100 by viewing display device 120 outside crawler dozer 100. The operator can also remotely operate crawler dozer 100 while watching display device 120.

In the above description of the embodiments, crawler dozer 100 comprising excavating blade 2 and ripper apparatus 10 has been described as an example of a work machine. Crawler dozer 100 may include other types of rear work implements instead of ripper apparatus 10. For example, crawler dozer 100 may comprise a winch behind body 1, and eighth camera 58 may be configured to capture an image in a range including the winch.

Display device 120 may not be disposed outside crawler dozer 100. For example, in crawler dozer 100 in which cab 9 is an operator's cabin, display device 120 of an embodiment may be disposed in the cabin, and video controller 60 mounted on crawler dozer 100 may cause display device 120 to display a captured image. The display system of the embodiment may be applied not only to a remotely controlled, unmanned work machine but also to a manned work machine in which an operator aboard the work machine operates the work machine. By monitoring display device 120, the operator aboard the work machine can grasp the attitude of ripper apparatus 10 without looking back.

The work machine is not limited to crawler dozer 100. For example, the concept of the present disclosure may be applied to other types of work machines, such as a motor grader comprising a blade between front and rear wheels and a ripper apparatus behind the body. When the work machine is an exclusively remotely controlled, unmanned work machine, the work machine may not include cab 9.

While the present invention has been described in embodiments, it should be understood that the embodiments disclosed herein are illustrative and non-restrictive in any respect. The scope of the present invention is indicated by the terms of the claims, and any modifications within the meaning and scope equivalent to the claims are intended to be encompassed. 

What is claimed is:
 1. A work machine comprising: a body; a ripper apparatus that is disposed rearward of the body; and an imaging device that is mounted to the body and captures an image of the ripper apparatus, wherein the ripper apparatus includes a shank, a ripping tip that is attached to an end of the shank, a beam that supports the shank, and a ripper arm that interconnects the body and the beam, and the imaging device images the ripper apparatus sideways and captures an image in a range including at least a portion of the shank, at least a portion of the beam, and at least a portion of the ripper arm.
 2. The work machine according to claim 1, wherein the ripper apparatus further includes a tilt cylinder that causes the ripping tip to reciprocate in a direction toward the body and a direction away from the body, and the imaging device captures an image in a range including at least a portion of the tilt cylinder.
 3. The work machine according to claim 1, wherein the ripper apparatus further includes a lift cylinder that causes the ripping tip to move up and down, and the imaging device captures an image in a range including at least a portion of the lift cylinder.
 4. The work machine according to claim 1, wherein the imaging device images the ripper apparatus on a left side.
 5. The work machine according to claim 1, further comprising: a ripping tip imaging device that is mounted to the body and captures an image in a range including the ripping tip; and a rear imaging device that is mounted to the body and captures an image in a range including a range of a rear side of and rearward of the body.
 6. A display system comprising: the work machine according to claim 5; and a display device that simultaneously displays an image captured by the ripping tip imaging device, an image captured by the rear imaging device, and an image captured by the imaging device.
 7. The display system according to claim 6, wherein the display device is caused to display the image captured by the ripping tip imaging device, the image captured by the rear imaging device, and the image captured by the imaging device such that the images are aligned from left to right.
 8. The display system according to claim 6, wherein the display device is disposed outside the work machine. 